springboot整合mybatis（详解）

springboot整合mybatis

1，整体结构

2，需要的依赖

<dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.3</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.12</version> <scope>provided</scope> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.2.1</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.xmlunit</groupId> <artifactId>xmlunit-core</artifactId> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.4.6</version> </dependency> </dependencies> 

声明一下，web架构需要thymeleaf支持，而mybatis需要mybatis-spring-boot-starter支持，

3，新建application.yml文件

在resources目录下新建yml文件，用于存放数据库连接需要的一些数据，也可以不建，直接将这些数据放在application.properties文件下，不过格式得转换

spring: datasource: driver-class-name: com.mysql.jdbc.Driver url: jdbc:mysql://localhost:3306/weixin?serverTimezone=GMT%2B8&useSSL=true username: root password: zhs0 

4，在application.properties文件中加入：

#端口号 server.port=8080 #druid数据库连接池 type=com.alibaba.druid.pool.DruidDataSource #清除缓存 spring.thymeleaf.cache=false #配置mapper mybatis.mapper-locations=classpath:mapper/*.xml 

5,在pojo下的新建类UserLogin

package com.example.weixin_01.pojo; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; @Data @AllArgsConstructor @NoArgsConstructor public class UserLogin { 
    private String username; private String password; } 

6，新建数据库，名为weixin，名可以随意，不过要与application.yml文件中的一致

7,建表，名为userLogin

8,mapper层

新建UserLoginMapper接口

package com.example.weixin_01.mapper; import com.example.weixin_01.pojo.UserLogin; import org.apache.ibatis.annotations.Mapper; import org.springframework.stereotype.Repository; import java.util.List; @Mapper @Repository public interface UserLoginMapper { 
    //查询 public List<UserLogin> queryAll(); //添加数据 public int add(UserLogin userLogin); //根据用户名查询数据 public UserLogin queryByName(String username); } 

9,在resources目录下新建mapper目录，并在这个目录下新建UserLoginMapper.xml文件，并在application.properties中注册该组件，前面已经注册

 
     <mapper namespace="com.example.weixin_01.mapper.UserLoginMapper"> <select id="queryAll" resultType="com.example.weixin_01.pojo.UserLogin"> select * from userLogin  
     select> <insert id="add" parameterType="com.example.weixin_01.pojo.UserLogin"> insert into userLogin values (#{username},#{password})  
      insert> <select id="queryByName" resultType="com.example.weixin_01.pojo.UserLogin"> select * from userLogin where username = #{username}  
       select>  
        mapper> 

10，测试

在test文件中，先测试是否能联通数据库，可以自己在数据库中插入一个数据，然后测试时查询全部，看看能否将自己插入的数据查询出来，如果可以，则数据库连接这部分就没问题

package com.example.weixin_01; import com.example.weixin_01.mapper.UserLoginMapper; import com.example.weixin_01.pojo.UserLogin; import org.junit.jupiter.api.Test; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import javax.sql.DataSource; import java.sql.Connection; import java.sql.SQLException; import java.util.List; @SpringBootTest class Weixin01ApplicationTests { 
    @Autowired DataSource dataSource; @Test void contextLoads() throws SQLException { 
    System.out.println(dataSource.getClass()); Connection connection = dataSource.getConnection(); System.out.println(connection); //template模板，拿来即用 connection.close(); } @Autowired UserLoginMapper userLoginMapper; @Test public void toTest(){ 
    List<UserLogin> userLogins = userLoginMapper.queryAll(); userLogins.forEach(e-> System.out.println(e)); } } 

11,services层

package com.example.weixin_01.services; import com.example.weixin_01.pojo.UserLogin; import java.util.List; public interface UserLoginServicesI { 
    //查询 public List<UserLogin> queryAll(); //添加数据 public int add(UserLogin userLogin); //根据用户名查询数据 public UserLogin queryByName(String username); } 

UserLoginServicesImpl类

package com.example.weixin_01.services; import com.example.weixin_01.mapper.UserLoginMapper; import com.example.weixin_01.pojo.UserLogin; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.List; @Service public class UserLoginServicesImpl implements UserLoginServicesI { 
    @Autowired UserLoginMapper userLoginMapper; @Override public List<UserLogin> queryAll() { 
    return userLoginMapper.queryAll(); } @Override public int add(UserLogin userLogin) { 
    return userLoginMapper.add(userLogin); } @Override public UserLogin queryByName(String username) { 
    return userLoginMapper.queryByName(username); } } 

12,conteoller层

编写MyController类

package com.example.weixin_01.controller; import com.example.weixin_01.pojo.UserLogin; import com.example.weixin_01.services.UserLoginServicesImpl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.RequestMapping; @Controller public class MyController { 
    @Autowired UserLoginServicesImpl userLoginServicesImpl; @RequestMapping("/toLogin") public String toLogin(){ 
    return "login"; } @RequestMapping("/LoginSuccess") public String LoginSuccess(Model model, UserLogin userLogin){ 
    //先查询看该用户名是否存在 UserLogin userLogin1 = userLoginServicesImpl.queryByName(userLogin.getUsername()); if(userLogin1 != null){ 
    // 如果查询的用户不为空 System.out.println(userLogin1.toString()); return "success"; } else{ 
    //返回到登录页面 model.addAttribute("data","该用户不存在，请先注册"); return "login"; } } //登录界面 @RequestMapping("/toRegister") public String toRegister(){ 
    return "register"; } @RequestMapping("/RegisterSuccess") public String toRegisterSuccess(Model model,UserLogin userLogin){ 
    //将账号密码加入到数据库中 int add = userLoginServicesImpl.add(userLogin); System.out.println("数据插入成功！"); model.addAttribute("data","注册成功，请登录！"); return "login"; } } 

13，编写前端页面

<!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body style="background: aqua"> <div align="center"> <br><br><h2>登录界面</h2><br><br> <span th:text="${data}" style="text-color:red;font-size: 10px"></span> <form method="get" action="/LoginSuccess"> 用户名:<input type="text" name="username" placeholder="请输入用户名" required/><br><br> 密码：<input type="text" name="password" placeholder="请输入密码" required/><br><br> <input type="submit" value="登录"> </form> <br> <form method="get" action="/toRegister"> <input type="submit" value="注册"> </form> </div> </body> </html> 

2,register.html:注册页面

<!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body style="background: aqua"> <div align="center"> <br><br>注册界面<br><br> <form method="get" action="/RegisterSuccess"> 用户名:<input type="text" name="username" placeholder="请输入用户名" required/><br><br> 密码：<input type="text" name="password" placeholder="请输入密码" required/><br><br> 确认密码：<input type="text" name="password2" placeholder="请输入密码" required/><br><br> <input type="submit" value="注册"> </form> </div> </body> </html> 

3，success.html：成功界面

<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>success</h1> </body> </html> 

14，运行一下

15，输入用户名和密码

16，注册

17,验证